Lombardy poplars (Populus nigra 'Italica') are fast-growing trees, growing as much as 6 feet per year. This makes them a popular choice when people want "living wall" privacy screens or windbreaks in a hurry. Lombardy poplar trees are best known for their columnar form and unusual branching structure—the branches start close to the ground and grow upward, parallel to the trunk. The fall foliage is a yellow color, but these trees are not primarily grown for their autumn display value. The bark turns black and develops furrows as the tree ages. In past times, Lombardy poplars were used for visual interest and to line golf courses. George Washington planted them at Mount Vernon in hopes of having a fast-growing forest.